A specialist in modern Europe, diplomatic history, and the Holocaust, Arno Joseph Mayer was Dayton-Stockton Professor of History, Emeritus, at Princeton University. A self-proclaimed "left dissident Marxist", Mayer's major interests were in modernization theory and what he called "The Thirty Years' Crisis" between 1914 and 1945.

After fleeing the Nazi conquest of Europe in 1940, Mayer became a naturalized citizen of the United States and enlisted in the United States Army. During his time in the Army, he was trained at Camp Ritchie, Maryland and was recognized as one of the Ritchie Boys. He served as an intelligence officer and eventually became a morale officer for high-ranking German prisoners of war. He was discharged in 1946. He received his education at the City College of New York, the Graduate Institute of International Studies in Geneva and Yale University. He was professor at Wesleyan University (1952–53), Brandeis University (1954–58) and Harvard University (1958–61). He taught at Princeton University beginning in 1961.